Why Does the Pilot Light in My Heater Keeping Going Out?

Why Does the Pilot Light in My Heater Keeping Going Out?

If you use an older natural gas furnace to provide heat for your house, it probably has a standing pilot light to ignite the burners whenever the system turns on. When the furnace is working as it should, the pilot light will remain burning steadily throughout the season.

But a common problem that people with furnaces run into is a pilot light that keeps going out. An unlit pilot light means that the burners can’t come on and the furnace won’t work. (A device called a thermocouple is designed to recognize when the pilot light fails and then shut off the burner as a safety precaution.)

Our customers often call us because of a pilot light they can’t keep lit. Below are some of the reasons this might happen:

• Faulty thermocouple – The thermocouple detects when the pilot light is on, and sends an electric current to the gas line to keep a valve open. When the pilot light goes out, the loss of current shuts the valve and stops gas flow. But if the thermocouple has a fault, it may think the pilot light is out when it isn’t and shut off the gas—which will in turn cause the pilot light to go out. Repair technicians will need to replace the thermocouple.
• Dirty pilot tube – The pilot tube brings gas to the pilot light. If it becomes dirty, it will block the gas and there won’t be enough to keep the pilot light burning. Repair technician can inspect the tube and clean it if necessary.
• Aging furnace – In general, when a pilot light won’t stay lit, it’s a sign that the furnace is getting too old. Pilot lights are outdated technology, and if your furnace is more than 20 years old, a failing pilot light is usually an indication that you should have a new furnace—one that uses an electronic ignition system—installed in its place. Furnaces that don’t use pilot lights consume less gas and will help you save energy.

Russell’s Heating & Air Conditioning offers furnace repair service in Palm Springs, CA.